E-band microwaves are mainly used in the backhaul of mobile base stations. Base stations are widely deployed in urban areas and change with the landform and the city layout. Therefore, E-band microwave may be used to form a mesh network to connect the base stations. As shown in FIG. 1, a microwave node 2 is distributed in a base station cell 1 of a mesh network, and E-band microwave links are established among microwave nodes 2. To realize a link between two microwave nodes 2 that are far from each other, several intermediate microwave nodes may be disposed between the two nodes. An intermediate microwave node always needs to connect links from multiple directions, and therefore requires a multi-directional antenna.
FIG. 2 shows a multi-directional antenna supporting eight directions. An intermediate microwave node consisted of the multi-directional antenna implements the relay of microwave signals according to the need of service scheduling, to perform service scheduling. For example, an antenna 1 receives a microwave signal in one direction and sends the microwave signal to an antenna 4 in another direction, and then the antenna 4 transmits the microwave signal.
FIG. 3 illustrates a structure that implements a microwave relay in a prior art, where electrical cables are used to connect an antenna 1 and an antenna 4, and connect an antenna 2 and an antenna 5. The antenna 1 in one direction receives a microwave signal. The signal is amplified and frequency converted and then sent to the antenna 4 in another direction, and finally transmitted by the antenna 4. Because there is no physical electrical cables connection between the antenna 1 and the antenna 5, the signal received by the antenna 1 cannot be transmitted in the direction of the antenna 5. Because antennas in different directions are connected through fixed lines, the multi-directional antenna cannot schedule the service of a received signal freely according to the need of the service.
FIG. 4 illustrates another structure that implements a microwave relay in a prior art, where a multi-directional antenna is connected to an indoor unit (IDU) device 4. The IDU device 4 is capable of transmitting a microwave signal received by an antenna in one direction (such as an antenna 2) through an antenna in another direction (such as an antenna 7) to implement the scheduling of services. The service scheduling process includes: converting a microwave radio frequency (RF) signal to an intermediate frequency signal at first, then demodulating the intermediate frequency signal to obtain a service data stream, and finally scheduling the service at the service layer. Because scheduling is not performed directly at the intermediate frequency layer, an additional cost is caused.
During the implementation of the preceding application, the inventor finds at least the following weakness in the prior arts:
It is difficult for the prior microwave relay methods and apparatuses to implement free scheduling of signals at low costs.